Volume Fraction Of Coarse Aggregate Research Articles

Distributions of coarse aggregate and steel fiber in ultra-high performance concrete: Migration behavior and correlation with compressive strength

The vertical distribution of coarse aggregates and steel fibers in ultra-high performance concrete (UHPC) both at fresh and hardened states was investigated to unveil their migration behavior and the correlation with compressive strength. To fulfill this purpose, customized design of specimens and tailored test method were developed. Specimens with two sizes (3–5 mm and 5–10 mm) and varying content (0–50 %) of coarse aggregate and different volume fraction of steel fiber (0–2 %) were proportioned. It was found that higher amount of coarse aggregates was located in the lower part whereas more steel fibers and voids were observed in the upper region of the specimens. Increasing the content of coarse aggregates resulted in worsened uniformness of its distribution, while incorporating steel fibers up to 2 % by volume imposed negligible effects on the heterogeneity. Migration of different phases primarily occurred during the fresh state. Compressive strength of the specimens at the middle layers was up to 30 % higher than those at the top and bottom layers. The inferior compressive strength was primarily ascribed to the worsened distribution of CAs and higher voids in the top layer.

Investigation of damage and crack characteristics of epoxy modified recycled asphalt mixtures based on a three-dimensional meso-heterogeneous model

Epoxy asphalt has excellent fatigue resistance, making it a valuable addition to recycled asphalt mixtures. However, the lack of sufficient understanding of the cracking mechanism in epoxy-modified recycled asphalt mixtures (EMRAM) hinders its widespread application. The purpose of this paper was to investigate the damage and crack characteristics of EMRAM based on a three-dimensional meso-heterogeneous model. The coarse aggregates were first randomly generated using the secondary Delaunay algorithm. Meanwhile, the fracture parameters of each component material and asphalt-aggregate interface in EMRAM were tested through three-point bending tests and direct shear tests, respectively. Cohesive zone model elements were then inserted at the aggregates, asphalt mastic, and interfaces between different materials to establish a three-dimensional meso-heterogeneous model of EMRAM. Finally, based on the established model, the damage degree of each composition material in EMRAM was quantitatively analyzed to identify the vulnerable aspects of EMRAM during the crack propagation stage. Optimization strategies were proposed accordingly. The results demonstrated that the model established in this study can accurately represent the meso-heterogeneous of EMRAM and effectively simulate its cracking behavior. EMRAM was more susceptible to developing internal damage within the aggregates, followed by relatively noticeable damage at the interface and the internal regions epoxy-modified fine aggregate mastic. The cracking resistance of EMRAM showed a trend of initially increasing and then decreasing with an increase in the volume fraction of coarse aggregates with a size above 4.75 mm. The optimal range for the volume fraction of coarse aggregates in EMRAM was within 35–44 %. The fracture energy of EMRAM was improved by more than 30 % after gradation optimization compared to EMRAM with gradation at the median value of AC20. Within the designed service life, EMRAM durable pavement can save at least 30 % more in economic costs compared to ordinary asphalt concrete pavement.

Fracture criteria and initiation mechanism of concrete based on material configurational mechanics

AbstractIn this study, the interaction force between an in‐plane elliptical inclusion and a crack is evaluated using the Eshelby equivalent inclusion and material configurational force method. The toughening effect of coarse aggregates on concrete is investigated. The fracture criteria for mixed‐mode cracks based on the characteristics of the crack‐tip plastic zone assessed by the principal configurational stress difference are proposed and verified by experimental results in the literature. The fracture probability is then used to improve the fracture criteria, and the dimensionless factor associated with stress intensity factors is introduced to determine the fracture probability. Additionally, the volume fraction of coarse aggregates, the age and fatigue life of concrete are considered in the present fracture criteria. Theoretical studies show that the interaction between a crack and a hard or soft inclusion exhibits mutual repulsion and attraction. The size and shape of the crack‐tip plastic zones assessed by the Mises stress and the principal configurational stress difference are essentially the same. The fracture load envelopes increase with the increase in the volume fraction of coarse aggregates and the age of concrete and shrink with the increase in the life ratio.

Advancing service life estimation of reinforced concrete considering the coupling effects of multiple factors: Hybridized physical testing and machine learning approach

Chloride-induced corrosion is the primary factor that significantly impacts the service life of reinforced concrete structures. Therefore, it is crucial to investigate the transportation behavior of chloride ions within concrete structures to accurately estimate their service life. Previous studies have mostly examined the diffusion of chloride ions through physical tests on concrete specimens. Some data-driven models have also been developed to predict the chloride ion concentration at different depths in concrete structures. However, these prediction models often considered random factors in materials and the environment separately, neglecting their coupled effects. As a result, there can be a significant disparity between the predicted results and the actual test outcomes. To achieve a more precise evaluation of the service life, this study conducted a physical test to investigate the diffusion behavior of chloride ions in plain concrete specimens. Factors such as water-cement ratio (W/C), coarse aggregate volume fraction (v) (ratios of the mass of coarse aggregates to the total mass of concrete specimen), ratios of environmental temperature to maintenance standard temperature (T/T0), ratios of environmental humidity to maintenance humidity (h/h0), and ratios of exposure time to maintenance time (t/t0) were considered in the test. Based on the test results, machine learning approaches were employed to determine the influence of each factor on the chloride diffusion coefficient (D) and surface chloride concentration (Cs). Subsequently, a prediction model was developed using the second Fick's law, with the chloride ion concentration at each depth as the output and the aforementioned factors as the inputs. Furthermore, by analyzing the above results, the study examined the impacts of various factors on the service life of reinforced concrete structures. The findings indicate that W/C and v are the most significant factors affecting D and Cs. As W/C and T/T0 increase, both D and Cs also increase. Conversely, the volume fraction of coarse aggregate has a hindering effect on the diffusion of chloride ions in concrete structures. Additionally, the study explored the effect of each input factor on the service life of reinforced concrete structures considering the effect of the above factors. Overall, these findings provide valuable insights into improving the accuracy of estimating the service life of reinforced concrete structures by considering the coupled effects of materials and environmental factors.

A numerical model for predicting the drying shrinkage behavior of concrete under ultra-low relative humidity

The drying shrinkage caused by rapid water loss will pose a great threat to the safety of concrete structures, especially for those serviced in an extremely dry environment. However, the majority of reported research primarily focuses on drying shrinkage behavior of concrete under relative humidity (RH) ranging from 50% to 100%, and the corresponding drying shrinkage prediction models have poor applicability, leading to an unclear understanding of it under ultra-low RH (RH<40%). In this study, a numerical model, finite element model with cohesive elements, was proposed to better predict the drying shrinkage behavior of concrete, even under the RH of 20%. Initially, geometric models of concrete with varying coarse aggregate size ranges and volume fractions were established. Subsequently, based on the relationship between RH and humidity diffusion coefficient of concrete with different water-cement ratio (w/c), a drying shrinkage model was proposed to examine the corresponding shrinkage strain of concrete even under ultra-low RH conditions, and its validity was verified through comparison with reported experimental research. Utilizing the developed model, the effects of size range and volume fraction of coarse aggregate, and the w/c, on the drying shrinkage of concrete across a wide range of RH levels were systematically investigated. The results indicated that increasing the aggregate size range can only slightly inhibit drying shrinkage, while there is a marked inhibition effect on it (decrease by about 45% at most) for increasing the aggregate vol% or reducing w/c, even under ultra-low RH of 20%. Finally, grey relation analysis was employed to assess the inhibition weight of each parameter on the drying shrinkage, following this sequence in order: RH > w/c > coarse aggregate vol% > coarse aggregate range size. We also envision that the proposed model could provide feasible guidelines for the inhibition of concrete in ultra-dry regions.

Effects of the particle morphology and volume fraction of coarse aggregate on the mechanical properties of concrete

The morphology and volume fraction of coarse aggregate particles significantly influence the mechanical characteristics of concrete. This paper presents the development of a numerical model for pebble concrete by combining experiments with the discrete element method. The mesoscopic parameters between mortars and the contact surface between mortars and aggregates in the model were calibrated by comparing simulated stress–strain relationships with experimental data from pebble concrete. Subsequently, the model and mesoscopic parameters were validated by comparing them with experimental results. The obtained mesoscopic parameters were then utilized in the numerical modeling of uniaxial compression for single-shaped coarse aggregate concrete. Results showed that the peak stress of the elliptical aggregate concrete was 2.8 MPa higher than that of the oblate spherical aggregate concrete, leading to more cracks and severe damage in the former. Thus, elliptical aggregates proved more suitable as coarse aggregates for concrete than oblate spherical aggregates. Furthermore, the study investigated the influence of ellipsoidal aggregate volume fraction on concrete strength. The compressive strength reached the highest when the volume fraction of ellipsoidal aggregate was 57%. Therefore, the ideal coarse aggregate volume fraction was determined to be 57%. These results offer valuable insights into designing concrete mix proportions.

Effect of coarse aggregate content on the rheological and buildability properties of 3D printable concrete

Additive manufacturing in construction industry is gaining attention among both researchers and industries. The present study deals with the effect of coarse aggregate (CA) content on the performance of 3D printable concrete. The fresh and rheological properties of the designed concrete with 8 mm down sized CA were assessed. The rheological parameters for the material with varying coarse aggregate (CA) volume fraction from 0% to 50% were studied. There is limited literature on the effect of large sized CA on the printability of the concrete. The rheological properties were measured using in-house developed rheometer designed for concrete with CA. The concrete mix with CA content percentage 10%, 20%, 30%, 40% and 50% were compared with control mix (CA content 0%). The static and dynamic yield stress values for 20% and 30% CA content followed decreasing trend and when increased more than threshold limit of 30%, the yield stress values increased. It was observed that the mortar volume ratio, fine aggregate ratio with respect to CA influences the rheological properties and slump flow. Relationship between the slump flow value and static yield stress was fixed for the designed concrete. Extrusion based layer by layer printing of cementitious material without the support of form-work makes the material more prone to failure and qualitative approach to resist the failure of the material while printing is a key aspect in 3D concrete printing and this quality is termed as ‘buildability’. The challenge lies in designing a material which is flowable with minimum dynamic yield stress and increased structuration rate confirming that the material attains the yield strength once the printing is initiated. The concrete mix with flowability 180 mm to 190 mm was having good buildability and smooth extrusion. The buildability of the designed concrete mix was calculated using Kruger’s analytical model in terms of number of layers and validated the model by direct printing method. The printing parameters like printing speed and resting time was fixed for the concrete with 8 mm down sized aggregate. The concrete mix with 40% CA content showed better buildability with optimum static and dynamic yield stress values.

Multiscale Theoretical Model of Thermal Conductivity of Concrete and the Mesoscale Simulation of Its Temperature Field

Temperature field analysis is the precondition of studying the heat and mass transfer and durability of a concrete building; thermal conductivity is a key parameter that affects the distribution of the temperature field of concrete. Through reasonable assumptions and simplifications, the relationship between the micro-microscopic composition of concrete and its macroscopic thermal conductivity is established, and a multiscale theoretical model of thermal conductivity considering the influence of interface transition zone (ITZ) is proposed. The model can predict the thermal conductivities of concrete and its components at an arbitrary saturation. Subsequently, the influence of saturation, water-cement ratio, volume fraction and type of coarse aggregate, and sand ratio is researched. Moreover, according to the prediction results of the proposed model, a mesoscale simulation of the concrete temperature field is carried out. The results demonstrate that the presence of aggregate and ITZ leads to the isotherm deflection and abruption at the junction of the phases. Meanwhile, the heat flux density at the corners of the polygonal aggregate is significantly higher than at other positions; the phenomenon, first named the “corner effect” in the research, causes the temperature field distribution of concrete containing polygonal aggregates to be more uneven than that of circular and elliptical aggregates, and it is more likely to produce temperature-induced cracks. The research helps explain the influence mechanism of material components on the thermal conductivity of concrete and the distribution of its temperature field and provides a basis for the fine simulation of concrete thermal crack growth and creep at variable temperatures.

Analysis of influencing factors of pneumatic flow enhancement of pumped concrete based on discrete element method

It is known that, long-distance concrete pipeline transportation often causes pipe blocking accidents. For the problem of pipeline blockage, we have invented a swirl speed-increasing device. In this study, the discrete element method was used to calibrate the parameters of the contact model through the slump bucket experiment, and a discrete element model of horizontal pumping concrete was established. Based on the particle unit, the flow-promoting mechanism of the swirl speed-increasing device was studied, and the effects of the pumping speed, the volume fraction of coarse aggregate and the wind speed output of the device on the movement state of the particles and the flow-promoting distance were analyzed. The results show that the maximum velocity and flow-promoting distance of the particle unit increase with the increase of pumping speed and wind speed, and decrease with the increase of the coarse aggregate volume fraction. When the pumping speed and wind speed are large, the installation distance of the flow promoting device should be increased. When the volume fraction of concrete aggregate is large, the installation distance of the flow promoting device should be shortened. Our swirl speed-increasing device can solve the problem of pumping concrete pipeline blockage. The discrete element model of pumping concrete established in this study can well reflect the motion state of the concrete unit in the pipeline, which verifies the applicability of the discrete element model. The numerical simulation conclusion in this paper can avoid system energy waste and pipeline blockage caused by improper selection of device installation spacing.

Developing an artificial neural network model to predict the durability of the RC beam by machine learning approaches

The chloride diffusivity is a significant index to describe the degradation rate of concrete structures. At present, a lot of models have been proposed by previous studies to investigate the chloride diffusivity in concrete specimens. However, most of these models only consider the effect of exposure time, and erosion depth on the chloride diffusivity and ignore the uncertain factor in the environment. This may lead to a tremendous difference existed in the predicted-to-experimental ratios of all typical chloride diffusivity models. Machine learning approaches as potential alternative predictors are often used to cope with this bias. This paper adopted five contemporary ML approaches, namely, the backpropagation (BP) neural network, the decision tree (DT), the random forest (RF), the linear regression (LR), and ridge regression (RR) to explore the chloride diffusivity. Input features considered in this study are water-cement ratios, the thickness of concrete specimens, coarse aggregate fraction volume, ratios of environmental temperature to the maintenance standard temperature, and ratios of environmental humidity to the relative humidity. It was found that the backpropagation (BP) neural network is the most accurate prediction (85%) with the lowest root mean squared error. With this superiority, A study on the importance of the input parameters reveals that the volume fraction of coarse aggregate, water-cement ratios, the thickness of the protective layer, and ratios of environment humidity to the relative humidity are the most influential parameters on chloride diffusivity. In addition, a data-driven model was established to investigate the chloride diffusivity considering the effect of random factors both in material and environment. Compared with the test results, the results indicated that the prediction results are closer to the test results, which is helpful for in-depth exploring the durability of the concrete structures.

Modelling of Chloride Concentration Profiles in Concrete by the Consideration of Concrete Material Factors under Marine Tidal Environment

The corrosion of reinforcement induced by chloride ions is one of the most significant causes of durability deterioration for reinforced concrete (RC) buildings. The concrete material factors, including the water-to-cement ratio (w/c) of concrete, as well as the content, shape, particle grading, and random distribution of coarse aggregate embedded in mortar, have a marked effect on chloride transport performance within concrete. However, comprehensive consideration for the effects of both w/c and coarse aggregate performances on chloride diffusion characteristics in concrete is scarce, especially regarding the chloride diffusion model of concrete. In this paper, an indoor exposure experiment exploring chloride ions intruding into mortar and concrete specimens with w/c = 0.4, 0.5 and 0.6 was carried out, in order to acquire the chloride diffusion parameters for concrete three-phases composites. Based on the numerical algorithm of random generation and placement of two-dimensional random convex polygon coarse aggregate, mesoscopic numerical models for concrete, considering various coarse aggregate contents as well as grading, were established. Using the numerical simulation method of finite element analysis for chloride transport in cement-based materials, which can replace some of the exposure tests, the influences of w/c, coarse aggregate content and grading on chloride diffusion performance in concrete mesoscopic models were systematically probed. According to the Fick’s second law, a chloride diffusion model by the consideration of w/c, volume fraction of coarse aggregate (VFCA), and maximum size of coarse aggregate (MSCA) was developed to assess the chloride concentration profiles in concrete under arbitrary w/c, coarse aggregate content, and coarse aggregate grading conditions. Certainly, the precision accuracy for this proposed chloride diffusion model was validated. The research results can provide theoretical support for chloride erosion behavior and structural durability assessment of concrete with different mix proportions.

A two-phase design strategy based on the composite of mortar and coarse aggregate for 3D printable concrete with coarse aggregate

In this investigation, a two-phase design strategy based on the composite of mortar phase and coarse aggregate phase is proposed for designing 3D printable concrete (3DPC) with coarse aggregate. Coussot model and Krieger-Dougherty model were utilized to establish a quantitative relationship between the rheological property of 3DPC and the volume fraction of coarse aggregate, aiming to design 3DPC with coarse aggregate based on the mix proportion of printable mortar and thus facilitate the mixture design. It is found that the plastic viscosity of 3DPC with coarse aggregate is excessively high when the volume fraction of coarse aggregate reaches to a certain value, which is the main reason restricting the printability of 3DPC with coarse aggregate. The printability of 3DPC with coarse aggregate cannot be solely evaluated by yield stress, the plastic viscosity should be taken into consideration together with yield stress for evaluation as well.

Numerical simulation of steel corrosion in chloride environment based on random aggregate concrete microstructure model

The corrosion of steel bar in concrete structure under chloride environment is simulated considering the influence of concrete coarse aggregate. Firstly, the random polygonal coarse aggregate is generated, and the meso numerical cross-section of reinforced concrete is obtained. Then, based on Butler-Volmer equation, considering the coupling effect of diffusion and electrochemical corrosion, an electrochemical corrosion model of steel bar is established. Next, the accuracy of the model is verified by existing experimental data. Finally, the relationships between the volume fraction of coarse aggregate and corrosion morphology, steel corrosion quantity and corrosion process are gotten. The results show that the coarse aggregate causes irregular corroded section shape of the steel bar, and there are convexities and concavities on the corroded surface. The coarse aggregate can suppress the steel corrosion. As the volume fraction of coarse aggregate increases, the durations of the non-corrosive stage and the corrosion expansion stage extend.

Modeling coarse aggregate distribution in interfacial zone of new–old concrete in precast concrete structures

AbstractThere are a large number of interfacial zones of new–old concrete in precast concrete structures, and the wall effect causes the reduction of coarse aggregate in the interfacial zones, which leads to the weaker physical, mechanical and durability properties of this part. In the present paper, some new–old concrete specimens with different chiseled depths at the interfaces were made to simulate the wet joints of precast concrete structures. The distribution characteristics of the coarse aggregate volume fraction in the interfacial zones of new–old concrete specimens were obtained by DIP (Digital Image Processing) technology. The results show that the distribution of the coarse aggregate volume fraction in the interfacial zones is similar to a positive V‐shape (no chiseling) or partial V‐shape (chiseled interface), and is generally lower than that of the noumenons of new and old concrete (constant values). With the increase of chiseled depth, the valley point (i.e., the minimum value) of the distribution curve of coarse aggregate volume fraction in the interfacial zone will move upwards and offset toward the old concrete. When the offset reaches 2 mm from the interface, it remains stable. The multiple irregular cone‐shape small pits on the actual chiseled surface are abstracted into a single bulging slope pit, and the area ratio of new–old concrete on the cross section within the chiseled range is derived. On this basis, the model of the coarse aggregate volume fraction in the interfacial zone varied with the distance from the interface is proposed.

Experimental Study on Effect of Coarse Aggregate Volume Fraction on Mode I and Mode II Fracture Behavior of Concrete

ShearThis paper utilizes double-K fracture criterion to investigate the effect of aggregate volume fraction on the Mode I and II fracture behaviors of concrete experimentally. Wedge splitting tests and Mode II fracture tests for non-notched specimens were carried out simultaneously for 60 specimens which were prepared with coarse aggregate in different volume fractions of 19%, 25%, 31% and 37%. It was found from the experimental results that as the volume fraction of coarse aggregate increases from 19% to 37%, both the Mode I and II fracture toughness increase and the crack trajectory becomes more tortuous. Based on the double-K fracture criterion, the ratio of KIIC/KIC is herein clarified as KIIC/Kini IC and KIIC/Kun IC. It is found that the values of KIIC/Kini IC and KIIC/Kun IC are not constants for concrete, instead, they are logarithmically related to the aggregate volume fraction. With the increase of the coarse aggregate volume fraction from 19% to 37%, the values of KIIC/Kini IC decrease sharply from 18.9 to 6.29, whereas the values of KIIC/Kun IC increase from 2.15 to 2.84. Finally, from the maximum distance between adjacent aggregates in concrete, a general formulation was proposed and verified by the published data and our tests to reasonably estimate Mode I and II fracture toughness with different volume fractions of coarse aggregate.

Theoretical and experimental study on the electrical resistivity method for evaluating fresh concrete segregation

This paper aims to provide a theoretical foundation to support the application of the electrical resistivity method to in-situ monitoring segregation of fresh concrete. We proposed a new non-conducting sphere model and an electrical resistivity algorithm to study the correlation between the electrical resistivity and the volume fraction of coarse aggregates. Glass spheres with different sizes were used to replace coarse aggregates in validation experiments for neglecting the irregular surface of coarse aggregate particles. A modified rectangular column mold containing three pairs of electrodes at different heights was developed to evaluate the segregation of fresh concrete. The experimental results were also compared with those obtained by the conventional washing-sieving method. The applicability of the correlations between electrical resistivity values and volume fractions of coarse aggregates was confirmed. The segregation index obtained by the electrical resistivity method has a good linear correlation with the segregation coefficient obtained by the washing-sieving method. Therefore, the electrical resistivity method has a great potential for in-situ monitoring stability of fresh concrete during placement and compaction processes.

Study on the calculation of the paste thickness on coated coarse aggregate based on stereology

Coarse aggregates in concrete are wrapped by cement mortar. On the one hand, coarse aggregates are bonded by cement mortar; on the other hand, cement mortar is the medium of transferring force when the concrete is stressed. So the workabilityandstrengthofconcrete are influenced by paste thickness on coated coarse aggregate (PTCCA). But PTCCA is not easy to be measured and more discrete. Asasolution, the concepts of average paste thickness on coated coarse aggregate (APTCCA) and effective paste thickness on coated coarse aggregate (EPTCCA) were proposed. The discrete element software PFC3D was used to simulate the standard concrete cubes with different volume content and gradation of coarse aggregate. According to volume content and gradation of coarse aggregate, the equations for predicting the APTCCA and EPTCCA were proposed. The equation for predicting coarse aggregate area in two-dimensional (2D) section according to coarse aggregate volume content was proposed. The correction factor of irregular aggregate was discussed. The recycled brick coarse aggregate concrete cubes were designed to verify the equations established in this paper. The test results showed that: The prediction equation of coarse aggregate area in 2D section was established by volume fraction and diameter of coarse aggregate, the correlation coefficient between the predicted values and the true values was 0.9892. The prediction equation of EPTCCA was established by volume fraction and diameter of coarse aggregate, the correlation coefficient between the predicted values and the true values was 0.9867. The prediction equation of APTCCA was established by coarse aggregate volume fraction, the correlation coefficient between the predicted values and the true values was 0.9788. The average roundness of recycled brick coarse aggregate (RBCA) was 0.42 and the variance was 0.0176. The confidence intervals of roundness of RBCA was [0.41,0.43] with 95% reliability. The average equivalent roundness of RBCA was 0.83 and the variance was 0.003. The confidence intervals of equivalent roundness of RBCA was [0.81,0.84] with 95% reliability.

Effects of Coarse Aggregate Content and Salt Solution Concentration on Freeze–Thaw Damage in Concrete

AbstractFreeze–thaw (FT) damage is one of the main factors affecting the durability of concrete structures. This paper focused on the effects of the coarse aggregate volume fraction (CAVF) on FT da...

Heat transfer mechanism of glazed hollow bead insulation concrete

In this study, an improved random aggregate adding method was used to develop a microscopic model of glazed hollow bead insulation concrete (GHBIC), and the model's effectiveness was verified through a test. In addition, the heat transfer performance of GHBIC was also studied using the model. The effect of shape, volume fraction, and gradation of coarse aggregate as well as the volume fraction and gradation of glazed hollow bead on the effective thermal conductivity of this concrete was studied. The results show that the glazed hollow bead effectively blocked the heat flow channel of GHBIC. The smaller the particle size and the higher the volume, the blocking effect is more obvious. Finally, considering the fineness of glazed hollow bead, a mathematical model for the thermal conductivity of GHBIC was established.

A 3D FEM Mesoscale Numerical Analysis of Concrete Tensile Strength Behaviour

A three‐dimensional (3D) finite element method (FEM) based on an inserted cohesive element numerical analysis procedure was developed for concrete mesoscale systems on the ABAQUS platform with python scripts. Aggregates were generated based on dividing the existing geometrical element algorithms to randomize arbitrary spheres. Simultaneously, randomizations of the maximum aggregate size and uniform distributions of aggregate particles were also considered. An FEM for the mortar phase in concrete mesoscale systems was generated along with the interfacial transition zone (ITZ) by inserting a cohesive element. Numerical parameter analyses were performed for nine different concrete systems by varying the coarse aggregate volume fraction (α) and the ITZ tension strength (ITZ‐S). The mechanical performance of concrete systems with the coupling effects of α and ITZ‐S was evaluated for simulated tensile loading. The results of the numerical simulations for mechanical properties, such as the simulated tensile strengths and tension damage behaviour of concrete systems, were verified with experimental results. The proposed aggregate and ITZ generation approach and numerical simulation procedure can be used by researchers to better understand how aggregate volume fraction and ITZ strength affect the tensile behaviour of concrete mesoscale systems.